The invention relates generally to nanostructure arrays, and more specifically to nanorod arrays.
Nanotechnology is becoming increasingly important as a basis for the fabrication of various devices. Nanostructures, such as nanorods, nanoparticles, nanowires and nanotubes, may be employed in many integrated circuits. Nanostructure-based devices are generally characterized by dramatically reduced power and mass, while simultaneously having enhanced capabilities. One such device that may employ nanotechnology is a field emitting device which may include a field emitting assembly having a cathode and a nanostructure array. To a large extent, the efficiency of the field emitting device is dependent on the design of the nanostructure array.
Nanostructure arrays may be fabricated through electrodeposition into porous templates. For example, metal nanorods may be formed by electrodeposition in the pores of an anodic aluminum oxide (AAO) template. In these cases, the spacing between the nanorods, or the “pitch” of the nanorods, is determined by the pitch of the pores in the template. The pitch of the pores in the AAO template may depend on the conditions during anodization such as, choice of the electrolytes as well as the voltage applied during anodization. In effect, the pitch of the nanorods may be controlled by varying the conditions under which the pores are formed in the AAO template. However, suitable combinations of electrolyte and voltage for achieving pitch greater than about 1 micrometer are not known.
Accordingly, it may be advantageous to fabricate large area nanostructure arrays with large pitch in a controlled manner.